Suppose a parallelogram has base length $5 \text{ cm}$ and height $4 \text{ cm}$. What is the parallelogram's area?
Answer: ${b = 5\text{ cm}}$ ${h = 4\text{ cm}}$ ${b = 5\text{ cm}}$ ${h = 4\text{ cm}}$ $20$ By moving a slice of the parallelogram, we can see that its area is equal to that of a rectangle with the same base and height. area of rectangle $ = b \times h$ $A = 5 \times 4 = 20$